CAMARILLO, Calif. >> The average national price of a regular gallon of gasoline has dropped 4 cents in the last two weeks to $2.50.

Industry analyst Trilby Lundberg said Sunday that falling oil prices and strong production at U.S. refineries led to lower numbers at the pump. The drop during the two-week period ended Friday comes despite labor strikes at some refineries.

Los Angeles had the most expensive gas among cities surveyed in the Lower 48 states at $3.29. Charleston, South Carolina, had the cheapest at $2.11.

The average national price for midgrade gas was $2.71 and $2.87 for premium. Diesel stands at $2.97, down 5 cents.